How long does it take a man to make SGT?
USMC NCO Promotion Minimums
At the NCO grades of E-4 and E-5 the process becomes competitive, meaning there are only so many openings available.
At minimum you still have to meet time-in-service and time-in-grade requirements.
To make E-4 requires at least 12 months in the service and 8 months as an E-3.
To make sergeant (E-5) requires at least 24 months in the service and 12 months as an E4-.
In practice, most people spend a lot more time than the minimum of time getting up to these ranks.
The typical sergeant has anywhere from five to eight years of time in service.
Most when I was in never advanced beyond E-4 in one enlistment.(Army 1957) Navy was qualified advancement but you not only had to pass you had to not piss off your division officer for whatever reason.